The Cyclops a Vidicon project

Centralised area for notes about construction projects. Each project has its own sub-forum. In the sub-forums will be topics relevant to parts of that project (e.g., there might be a topic on CRT problems). If you start a construction diary, just post in the forum with your project name as the topic, and a moderator will create a sub-forum for your project.

Moderators: Steve Anderson, Dave Moll, Andrew Davie

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Fri Jun 15, 2018 3:19 pm

OK it ended up being a dead MPF102 ,i was thinking before i did a test on the circuit that it would more than likely be the old 2N2222A but it was fine ,lucky i got a few VHF FET transistors today to replace and test with ,so the preamp is working again .
Now i have got some sort of image up again i will take some readings .
I am starting look into recording side of things .....i have found my sync is locked on the recording computer i am recording with but it drifts a fair bit viewing it on this one i am typing on ..look into this .
If i have time today i will try and some thing up .
Last edited by Harry Dalek on Fri Jun 15, 2018 7:12 pm, edited 1 time in total.
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Steve Anderson » Fri Jun 15, 2018 4:30 pm

Hmmm, it's always a good idea to ask yourself, "Why did it fail? It was fine at the start." In builds like these it can be so many things...did a high voltage get into the FET from somewhere? Solder splashes, bad joints, an off-cut of wire floating around?...all the usual suspects. It's great when you find the culprit, when you don't it's an uneasy feeling.

Steve A.
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 3812
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Fri Jun 15, 2018 7:11 pm

Steve Anderson wrote:Hmmm, it's always a good idea to ask yourself, "Why did it fail? It was fine at the start." In builds like these it can be so many things...did a high voltage get into the FET from somewhere? Solder splashes, bad joints, an off-cut of wire floating around?...all the usual suspects. It's great when you find the culprit, when you don't it's an uneasy feeling.

Steve A.


Hi Steve
It was a Question that i asked my self i was thinking it was my variable supply i was running the circuit to high The FET is rated at 25v but i was only running at 12v , but you asking the Question and thinking more about it the input is isolated from the Target supply by a capacitor it is possible the cap i used is faulty or i ran the target voltage over its rated voltage, the Target voltage go's to around the 80 volts but normal running that's not used way lower i think ,i will have a look or just replace it just in case .....adjusting the target trimmer i could have caused a spark to jump in the capacitor to the FET. :roll: you got me there !
Give that a go before using it again .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Sat Jun 16, 2018 8:04 pm

Still some problems to work out but today have now replaced the Target to FET capaciitor and made sure it was rated at at least 100 volts now and did a quick test below in fast forward ... :wink:
Bit more contrast to this fast version and its small.
sat2.mp4
(1.79 MiB) Downloaded 153 times

Below normal speed ,i need to do a test card where i can focus to correctly instead of holding something so sorry for the bad focusing !

I need to frame the video and there's a slow line drift when i record the sync also a inverted sync video problem all due to the sound card ,i can invert the video before hand which has worked in the past ,live camera to software view seems fine reason for camera screen recording at the moment .
Attachments
1snapshot_100.png
1snapshot_100.png (90.03 KiB) Viewed 4236 times
Output_Merge(3).mp4
(20.68 MiB) Downloaded 292 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Sun Jun 17, 2018 6:57 pm

Been looking into better results from the cameras clock to stop my line drift being the clock is steady but off frequency ,the 7404 crystal oscillator i am using a is running at 388 hz not good enough 12 hz off ....adjusting it i can get it close to 400hz using a frequency meter and the sync bar as a test see how my adjustments on drifting are going but can never get it on 400hz ..
I made and tested a 4060 crystal oscillator as a replacement which gives a dead on 400 hz result so out with the old in with the new ,but i have used it on the PMT camera and it worked well there too ..i have lots of those handy could just about replace the clock and first 4040 in the DAC with one of these .
Any case the clock giving me the lower NBTV line rates out of the DAC is what i want here for now .
I used a 74HC4060 ..running at 5 volts
Attachments
Screen 00002.jpg
Screen 00002.jpg (14.17 KiB) Viewed 4217 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Fri Jun 22, 2018 7:25 pm

Have not posted for a while every thing going well with the camera no problems just steps to do .
Mounted the focus coil pot on the back panel i will put a brightness control there as well .
Did try adjusting the dual voltage to the deflection amplifiers to see the effect on the target screen size, found no change until it went to low and cut out .
I will try adjusting the current instead see if that causes the wanted increase screen adjustment might be easier to adjust this right to the deflection coils thinking out aloud ! :roll:
Same as circuit below apart from 470uf cap not used and the current limiting resistor is 5 ohm 10 ohm on the H and v side
But first i am getting the power supply board mounted having the panel focus pot on the back panel good to get this out of the way .
I also have to look into the Gamma side this needs better blacks ,and adding the new 3.2 Mhz crystal clock ..so a few changes i will get to when i have some spare time .
Attachments
addtext_com_MDA1OTQyNjgxNDg-crop.jpg
addtext_com_MDA1OTQyNjgxNDg-crop.jpg (138.21 KiB) Viewed 4180 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Sat Jun 30, 2018 5:18 pm

I am bit behind on what i wanted to do by now most of the boards are mounted and got rid of the old rca preamp housing taking up room .
Wiring looks messy still but the wiring is mostly in umbilical wiring bundles i will place those neater bit later /
Did a few more tests today below ,due to my slow poke pace i have still to mount the new crystal clock so no recordings yet just live capture .
DSCN9784.JPG
DSCN9784.JPG (477.05 KiB) Viewed 4139 times

Covered the Vidicon with card board foil an tape for a better yoke hole fit and light proof it better .
DSCN9771.JPG
DSCN9771.JPG (406.7 KiB) Viewed 4139 times

DSCN9773.JPG
DSCN9773.JPG (180.7 KiB) Viewed 4139 times

Had to make sure every thing still worked mounted the boards looked good only had to adjust the focus side of it ,had the yoke turned on side one way or another so tests had to be done with upside down or side ways for the test cards .
Every thing again today 32 line
DSCN9788.JPG
DSCN9788.JPG (121.72 KiB) Viewed 4139 times

DSCN9787.JPG
DSCN9787.JPG (102.29 KiB) Viewed 4139 times

DSCN9780.JPG
DSCN9780.JPG (164.87 KiB) Viewed 4139 times

DSCN9781.JPG
DSCN9781.JPG (107.71 KiB) Viewed 4139 times

DSCN9775.JPG
DSCN9775.JPG (187.66 KiB) Viewed 4139 times


When i first got it going today i had the focus so it could only focus closer in this case it gives very good greys to the image .
DSCN9777-crop.JPG
DSCN9777-crop.JPG (196.3 KiB) Viewed 4139 times

with a more distance focus bit washed out again .
Attachments
DSCN9797.JPG
DSCN9797.JPG (151.99 KiB) Viewed 4139 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Sun Jul 01, 2018 6:40 pm

Today i looked into how accurate the new crystal clock is its pretty much showing dead on 400hz for 32 line via pin 2 of the 74hc4060 on my frequency meter it seems correct checking it for sync drift on Garys software Big picture on hes scope ....but on Doms it shows a slight drift also same on Garys NBTV version 1 software so to me there must be some correction going on on the Big Picture versions might need another Trimmer capacitor value or a second to replace the other fixed cap .Using the circuit a few posts ago ...least it is at the moment very usable once i test the camera again .
Garys big picture result below i see a correction happening

On Doms it does not correct the slight off frequency so drift must be a 1 hz or 2 off .
any case something that needed to be looked into today .
Attachments
12018_x264.mp4
(88.19 KiB) Downloaded 198 times
22018_x264.mp4
(134.68 KiB) Downloaded 197 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Klaas Robers » Sun Jul 01, 2018 9:15 pm

It is more likely that the software ferequency of your computer has a slight deviation. That is the reason that sync pulses are needed to keep the (big) picture stable.

But if you want to have an idea about the precision, time yourself how long it takes until the black bar is back in the same position. If that is 100 seconds (I gues that it is much more) then it is 40 000 pulses of the 400 Hz signal. One pulse less or more on the 40 000 pulses. So the deviation of the frequency 1 / 40 000, or 2.5 10^-5, which is reasonable for a crystal oscillator.

There is no reason to adjust this for your aplication in a camera. Besides that, if you do so, you adjust it to the clock frequency of the PC, which is also just a non adjusted crystal ascillator.

I would be happy with the result.
User avatar
Klaas Robers
Frankenstein was my uncle.
 
Posts: 1436
Joined: Wed Jan 24, 2007 8:42 pm
Location: Valkenswaard, the Netherlands

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Sun Jul 01, 2018 10:56 pm

Klaas Robers wrote:It is more likely that the software ferequency of your computer has a slight deviation. That is the reason that sync pulses are needed to keep the (big) picture stable.


I will check that with the second PC just see what happens doing the same test on the original pc i recorded this on ,i didn't have the other software handy on it to do it then and there .

But if you want to have an idea about the precision, time yourself how long it takes until the black bar is back in the same position. If that is 100 seconds (I gues that it is much more) then it is 40 000 pulses of the 400 Hz signal. One pulse less or more on the 40 000 pulses. So the deviation of the frequency 1 / 40 000, or 2.5 10^-5, which is reasonable for a crystal oscillator.


It is yes pretty stable just a touch off your calculations show how well its doing .
i am a bit fussy as i managed to lock it dead on in the PMT camera using the same design that was just a slight adjustment with a trimmer capacitor this one is a touch off in the value i used before ...but if i am only matching it to one computer i can find out by the frequency recording some one else can have a look its pulse width is not adjusted just out of the 4060 pin 2 for now , i will feed the 3.2768 MHZ crystal frequency to the main circuits .

There is no reason to adjust this for your aplication in a camera. Besides that, if you do so, you adjust it to the clock frequency of the PC, which is also just a non adjusted crystal ascillator.

I would be happy with the result.


OH yes as it is now it is pretty usable for video recording at 32 line using only BIG PICTURE software there would be no sync movement ,I would like to move up to 64 line when i know i can get a good 32 line recording ....
i uploaded today]s recording here again it just out of pin 2 of the 4060 have not adjusted the pulse width ..i would be interested what results others see in sync lock or not if it is a pc clock or software problem .
Attachments
sunn1.wav
(2.74 MiB) Downloaded 114 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Mon Jul 02, 2018 8:35 pm

Being a fussy bugger I swapped the capacitor trimmer to just try to match my pmt camera crystal clock .
52018.wav
400hz pin2 4060 crystal clock
(2.71 MiB) Downloaded 121 times

With the free software tools for audio frequency testing my procedure here is to use this free oscilloscope program shown below and watch the leading edge of the 400hz square wave on the scope setting you can see adjusting the clocks trimmer any movement swing in the frequency as the leading edge line will of cause it to move slowly or fast if you are off but with patience and slight trimmer adjustments you can pretty much nearly get it dead on ..and also view on its Real time analyzer and frequency meter how stable it is that is shown below might have to view full screen for that .
https://www.zeitnitz.eu/scope_en
i was testing the yellow cap trimmer here i will now solder it neater in place .
DSCN9801.JPG
DSCN9801.JPG (98.9 KiB) Viewed 4110 times

Below makes for a boring video as nothing moves much but that's what i was aiming for ! i like using Doms software as it very fussy on stable sync or correct frequency so its good to test this sort of thing ...
i noticed after loading i had it on one of the NBSC standards but same result double checking on stand NBtv 32 line .
Attachments
m2j18_x264.mp4
(543.34 KiB) Downloaded 197 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Klaas Robers » Tue Jul 03, 2018 7:30 pm

Yes, it is difficult to tune a crystal oscillator exactly onto his precise frequency. The main reason is that a frequency counter ALSO runs on a crystal. I had this problem manifest when I wanted to have a clock with a synchronous motor that should run on the 60 Hz American grid. As our grid is 50 Hz I had to generate the 60 Hz sine wave using a PIC-controller. And although the PIC generated a fine sine wave in the software I made, the frequency is dependent on the crystal oscillator of the PIC.

For a stable time reading, 1 second / month, the crystal frequency should be 20 000 032 Hz. The crystal oscillator of my frequency counter was specified on 10^-6, that is 20 Hz on 20 MHz. so the 32 Hz reading is too much asked for my counter.

Then I built a 10 MHz oscillator that is locked to GPS. After several minutes this gives a 10 MHz with a deviation of less than 0,1 Hz and that is better than my counter can display (counting time 10 sec). So I can check my counter, take his deviation in account and measure and adjust the oscillator of the PIC. You see how fast you come into problems of precision.

What you did now is to match the frequency of your sync generator to the frequency of your computer. For your experiments this may be good enough.
User avatar
Klaas Robers
Frankenstein was my uncle.
 
Posts: 1436
Joined: Wed Jan 24, 2007 8:42 pm
Location: Valkenswaard, the Netherlands

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Tue Jul 03, 2018 8:11 pm

Klaas Robers wrote:Yes, it is difficult to tune a crystal oscillator exactly onto his precise frequency. The main reason is that a frequency counter ALSO runs on a crystal.


Hi Klass
I think i have learnt from around the time of the pmt camera that the higher the frequency the more difficult it is to keep this stable ,pretty much comes down to the circuit design and how good your test gear is to measure the result .
I can understand your frustration !
I could of looked right at the crystal frequency but i think that would of been harder , using that using the 4060 it comes down to being able to match the 400 hz output to the display stable on the software which is very handy .

What you did now is to match the frequency of your sync generator to the frequency of your computer. For your experiments this may be good enough.


Yes seems good enough no sync roll ,i can't say over some time there would be no movement but yes good enough for recordings very happy with that result yesterday ..once i hook it up i will do some camera recordings ...i should let it run for an hour line up the sync bar and see how much movement there is .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Thu Jul 05, 2018 8:09 pm

Today i cleaned up the wiring a bit which you might not notice as there's a fair bit ,added mounted the new clock and did some quick tests with out adjusting any thing apart from focus .
I removed the manual yoke position controls as they were in the way and i did want them here .
Still have to position and and bolt in the Vidicon yoke housing which the vidicon yoke rotates and moves in and out init , depends on the range of focus distance works out best no reason to drill drilled holes till i work that out .
i also need to get some more light which pretty much needs to increase as distance increase's i have found out .
DSCN9811.JPG
DSCN9811.JPG (280.96 KiB) Viewed 4029 times

DSCN9809.JPG
DSCN9809.JPG (92.42 KiB) Viewed 4029 times

Back on the Clock subject at first tried to get the 3,2mhz clock output from either side of the crystal that was a mistake made the trimmer cap unable to adjust the clock frequency any more and was stuck with an amount of drift .
So as below pin 10 was the solution but in the mean time i had adjusted the trimmer to find out why and that's why i have a touch of drift again in the videos below ......... i will look at it and readjust it better next time , slight roll down i notice now .
addtext_com_MDIxMTI5MzI0NzA.jpg
addtext_com_MDIxMTI5MzI0NzA.jpg (20.08 KiB) Viewed 4029 times

I have noticed a problem and that is a double image and up side down in the top of the frame ,i have not yet gone back and have a look at the deflection signals as they can distort if i have the position controls off ,it is a strange one for me and wondering why ,i was at first thinking it might be the lens ,might be as Klass suggestion on over deflection scanning, it might also be causing this problem .
1.jpg
1.jpg (6.88 KiB) Viewed 4029 times

6.jpg
6.jpg (6.31 KiB) Viewed 4029 times


DSCN9804.JPG
DSCN9804.JPG (201.43 KiB) Viewed 4029 times

64 line viewing on 32 line double image but also shows the double image per frame

Here i tried 64 line on Doms 64 line nbtv standard software ,notice the sync drift more here .
DSCN9808.JPG
DSCN9808.JPG (66.95 KiB) Viewed 4029 times

Attachments
thur12018_x264.mp4
(3.2 MiB) Downloaded 177 times
hhead2_x264.mp4
(5.06 MiB) Downloaded 161 times
catthursday2_x264.mp4
(4.17 MiB) Downloaded 186 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: The Cyclops a Vidicon project

Postby Harry Dalek » Fri Jul 06, 2018 1:31 pm

Today here i just rotated the yoke and got more lighting now that helps !
Still problems with the video signal result but lighting is now good enough
32 line below
friday672018.wav
(22.79 MiB) Downloaded 128 times


A litte test at 64 Line


I will have a look if i can adjust it better and look at that deflection again .
Attachments
fridayvidiconme_x264.mp4
(3.92 MiB) Downloaded 158 times
frdayvidicon1_x264.mp4
(12.73 MiB) Downloaded 164 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 4054
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

PreviousNext

Return to Construction Diaries - Electronic Televisions

Who is online

Users browsing this forum: No registered users and 1 guest

cron